This research project will evaluate: A. The effect of desferrioxamine administration from an early age, starting concurrently with the transfusion program, in the prevention of iron overload-induced damage of heart, liver and endocrine glands of thalassemia major patients aged less than 6 years. B. The effect of desferrioxamine on the evolution of chronic active or persistent transfusion hepatitis,, a complication often encountered in children receiving transfusion therapy. C. The effect of desferrioxamine in a group of patients with thalassemia intermedia who are not receiving transfusion. Up to date 16 thalassemia major children aged less than 6 years (A), II thalassemia major children with chronic persistent (3) or active (4) hepatitis (B) and 6 patients with non-transfusion-dependent thalassemia intermedia (C) have been included in this trial; consisting in daily desferrioxamine x12 hour subcutaneous infusion at the most effective dose, in terms of iron chelation (40-80mg/Kg for children less than 6 years and 60-100mg/Kg up to a maximum of 2gr/day in patients with chronic hepatitis or thalassemia intermedia). All the patients will have once a month pediatric and hematologic evaluation incuding ferritin determination and twice a year radiological, biochemical, virological, endocrinological, cardiological and ophthalmological evaluation including slit lamp examination of the lens.